Fixed tests

src/Avalonia.Controls/TopLevel.cs

@@ -129,7 +129,7 @@ namespace Avalonia.Controls
         public Size ClientSize
         {
             get { return _clientSize; }
-            private set { SetAndRaise(ClientSizeProperty, ref _clientSize, value); }
+            protected set { SetAndRaise(ClientSizeProperty, ref _clientSize, value); }
         }
 
         /// <summary>
@@ -216,6 +216,8 @@ namespace Avalonia.Controls
         protected virtual void HandleResized(Size clientSize)
         {
             ClientSize = clientSize;
+            Width = clientSize.Width;
+            Height = clientSize.Height;
             LayoutManager.Instance.ExecuteLayoutPass();
             PlatformImpl.Invalidate(new Rect(clientSize));
         }

src/Avalonia.Controls/WindowBase.cs

@@ -137,7 +137,10 @@ namespace Avalonia.Controls
                 Width = clientSize.Width;
                 Height = clientSize.Height;
             }
-            base.HandleResized(clientSize);
+            ClientSize = clientSize;
+            LayoutManager.Instance.ExecuteLayoutPass();
+            PlatformImpl.Invalidate(new Rect(clientSize));
+
         }
 
         /// <summary>

tests/Avalonia.Controls.UnitTests/TopLevelTests.cs

@@ -86,7 +86,6 @@ namespace Avalonia.Controls.UnitTests
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
                 var impl = new Mock<ITopLevelImpl>();
-                impl.SetupProperty(x => x.ClientSize);
                 impl.SetupProperty(x => x.Resized);
                 impl.SetupGet(x => x.Scaling).Returns(1);